Yamaha YZF-R125 Owners Manual: Motorcycle care and storage

Troubleshooting charts

Starting problems or poor engine performance Starting problems or poor engine performance Engine overheating WARNING Do not remove the radiator cap when the engine and radiator are hot. S ...

Matte color caution

NOTICE Some models are equipped with matte colored finished parts. Be sure to consult a Yamaha dealer for advice on what products to use before cleaning the vehicle. Using a brush, harsh ch ...

Other materials:

Checking the primary drive gear
1. Remove: Primary drive gear Refer to "BALANCER GEAR" on page 5-53. 2. Check: Primary drive gear Damage/wear  Replace the primary drive gear and clutch housing as a set. Excessive noise during operation Replace the primary drive gear and clutch housing as a set ...

Checking the friction plates
The following procedure applies to all of the friction plates. 1. Check: Friction plate Damage/wear Replace the friction plates as a set. 2. Measure: Friction plate thickness Out of specification Replace the friction plates as a set. NOTE: Measure the friction plate ...

Checking the cylinder head
1. Eliminate: Combustion chamber carbon deposits (with a rounded scraper) NOTE: Do not use a sharp instrument to avoid damaging or scratching: Spark plug bore threads Valve seats 2. Check: Cylinder head Damage/scratches   Replace. Cylinder head water jacket Min ...